We found 18 dictionaries that define the word summing:

General (13 matching dictionaries)

1. summing: Merriam-Webster
2. summing: Oxford Learner's Dictionaries
3. summing: Collins English Dictionary
4. summing: Vocabulary.com
5. Summing, summing: Wordnik
6. summing: Wiktionary
7. summing: Dictionary.com
8. Summing: Wikipedia, the Free Encyclopedia
9. Summing: Online Plain Text English Dictionary
10. Summing: AllWords.com Multi-Lingual Dictionary
11. summing: Webster's 1828 Dictionary
12. summing: FreeDictionary.org
13. summing: TheFreeDictionary.com

Business (1 matching dictionary)

14. summing: Legal dictionary

Computing (1 matching dictionary)

15. summing: Encyclopedia

Miscellaneous (1 matching dictionary)

16. summing: Idioms

Science (1 matching dictionary)

17. summing: PlanetMath Encyclopedia

Slang (1 matching dictionary)

18. summing: Urban Dictionary

(Note: See sum as well.)

Definitions from Wiktionary (summing) ▸ noun:  The act or result of addition; a sum. Similar: summation, addition, adding, summing-up, summarisation, sum-up, subsumption, addn., summarization, inclusion, more... Opposite: subtracting, deducting, reducing Phrases: summing up, summing amplifier, more... Adjectives: final, general, brief, simple, own, best, mere, fair, judicial, admirable, impartial Colors:     sunset orange,     golden yellow,     coral pink,     sky blue,     lavender, more... ▸ Words similar to summing ▸ Usage examples for summing ▸ Idioms related to summing ▸ Wikipedia articles (New!) ▸ Popular adjectives describing summing ▸ Words that often appear near summing ▸ Rhymes of summing ▸ Invented words related to summing